diff options
author | Aaron Campbell <aaron@cvs.openbsd.org> | 2001-05-01 18:49:36 +0000 |
---|---|---|
committer | Aaron Campbell <aaron@cvs.openbsd.org> | 2001-05-01 18:49:36 +0000 |
commit | dad8f0f1db351ce59bf72b9bd6181c1d6a12577b (patch) | |
tree | a25a8bb54af082be8a580eea5383c781fef9e83e /lib/libc/gen | |
parent | bc63ffcd1f43abe4f2049f21506f9167a2cb7cfa (diff) |
Use pread() to avoid lseek() abuse, from art's todo list. Tested with
config(8) UKC; millert@ ok
Diffstat (limited to 'lib/libc/gen')
-rw-r--r-- | lib/libc/gen/nlist.c | 39 |
1 files changed, 15 insertions, 24 deletions
diff --git a/lib/libc/gen/nlist.c b/lib/libc/gen/nlist.c index 1efa698bff2..252254335ef 100644 --- a/lib/libc/gen/nlist.c +++ b/lib/libc/gen/nlist.c @@ -32,7 +32,7 @@ */ #if defined(LIBC_SCCS) && !defined(lint) -static char rcsid[] = "$OpenBSD: nlist.c,v 1.36 2001/02/03 02:37:27 art Exp $"; +static char rcsid[] = "$OpenBSD: nlist.c,v 1.37 2001/05/01 18:49:35 aaron Exp $"; #endif /* LIBC_SCCS and not lint */ #include <sys/types.h> @@ -67,26 +67,27 @@ __aout_fdnlist(fd, list) { register struct nlist *p, *s; register char *strtab; - register off_t symoff; + register off_t symoff, stroff; register u_long symsize; register int nent, cc; int strsize, usemalloc = 0; struct nlist nbuf[1024]; struct exec exec; - if (lseek(fd, (off_t)0, SEEK_SET) == -1 || - read(fd, &exec, sizeof(exec)) != sizeof(exec) || + if (pread(fd, &exec, sizeof(exec), (off_t)0) != sizeof(exec) || N_BADMAG(exec) || exec.a_syms == NULL) return (-1); + stroff = N_STROFF(exec); symoff = N_SYMOFF(exec); symsize = exec.a_syms; /* Read in the size of the string table. */ - if (lseek(fd, N_STROFF(exec), SEEK_SET) == -1) - return (-1); - if (read(fd, (void *)&strsize, sizeof(strsize)) != sizeof(strsize)) + if (pread(fd, (void *)&strsize, sizeof(strsize), stroff) != + sizeof(strsize)) return (-1); + else + stroff += sizeof(strsize); /* * Read in the string table. We try mmap, but that will fail @@ -95,13 +96,13 @@ __aout_fdnlist(fd, list) */ strsize -= sizeof(strsize); strtab = mmap(NULL, (size_t)strsize, PROT_READ, MAP_COPY|MAP_FILE, - fd, lseek(fd, 0, SEEK_CUR)); + fd, stroff); if (strtab == MAP_FAILED) { usemalloc = 1; if ((strtab = (char *)malloc(strsize)) == NULL) return (-1); errno = EIO; - if (read(fd, strtab, strsize) != strsize) { + if (pread(fd, strtab, strsize, stroff) != strsize) { nent = -1; goto aout_done; } @@ -125,16 +126,13 @@ __aout_fdnlist(fd, list) p->n_value = 0; ++nent; } - if (lseek(fd, symoff, SEEK_SET) == -1) { - nent = -1; - goto aout_done; - } while (symsize > 0) { cc = MIN(symsize, sizeof(nbuf)); - if (read(fd, nbuf, cc) != cc) + if (pread(fd, nbuf, cc, symoff) != cc) break; symsize -= cc; + symoff += cc; for (s = nbuf; cc > 0; ++s, cc -= sizeof(*s)) { char *sname = strtab + s->n_un.n_strx - sizeof(int); @@ -321,10 +319,8 @@ __elf_fdnlist(fd, list) int usemalloc = 0; /* Make sure obj is OK */ - if (lseek(fd, (off_t)0, SEEK_SET) == -1 || - read(fd, &ehdr, sizeof(Elf_Ehdr)) != sizeof(Elf_Ehdr) || - !__elf_is_okay__(&ehdr) || - fstat(fd, &st) < 0) + if (pread(fd, &ehdr, sizeof(Elf_Ehdr), (off_t)0) != sizeof(Elf_Ehdr) || + !__elf_is_okay__(&ehdr) || fstat(fd, &st) < 0) return (-1); /* calculate section header table size */ @@ -420,14 +416,9 @@ __elf_fdnlist(fd, list) if (symoff == 0) goto elf_done; - if (lseek(fd, (off_t) symoff, SEEK_SET) == -1) { - nent = -1; - goto elf_done; - } - while (symsize > 0) { cc = MIN(symsize, sizeof(sbuf)); - if (read(fd, sbuf, cc) != cc) + if (pread(fd, sbuf, cc, symoff) != cc) break; symsize -= cc; symoff += cc; |